const fs = require('fs')

// 方法一，读取写入
let data = fs.readFileSync('./原文件.mp4')
fs.writeFileSync('./copy.mp4', data)

// 方法二，流式操作
let rs = fs.createReadStream('./原文件.mp4')
let ws = fs.createWriteStream('./copy 2.mp4')
rs.on('data', chunk => {
  ws.write(chunk)
})